AstraZeneca (AZ) and Daiichi Sankyo’s Enhertu (trastuzumab deruxtecan) has been approved by the European Commission (EC) as a monotherapy for adult patients with advanced HER2-positive gastric or gastroesophageal junction (GEJ) adenocarcinoma who have received a prior trastuzumab-based regimen, the companies announced.
The decision, which follows a recommendation from the European Medicines Agency’s Committee for Medicinal Products for Human Use, makes Enhertu the first HER2-directed medicine to be approved for gastric cancer in the EU in more than a decade.
The EC based its decision on results from the DESTINY-Gastric02 and the DESTINY-Gastric01 phase 2 trials.
In DESTINY-Gastric02, updated results showed treatment with Enhertu resulted in a confirmed objective response rate (ORR) of 41.8%, with a median duration of response (DoR) of 8.1 months and median overall survival (OS) of 12.1 months.
In DESTINY-Gastric01, Enhertu-treated patients experienced an ORR of 40.5% versus 11.3% with chemotherapy (irinotecan or paclitaxel). The study also demonstrated a median DoR of 11.3 months with Enhertu versus 3.9 months with chemotherapy, and a median OS of 12.5 months in Enhertu-treated patients versus 8.4 months in the placebo group.
In both trials, the safety profiles observed in patients treated with Enhertu were consistent with those seen in other trials of Enhertu, the companies reported, with no new safety signals identified.
Gastric cancer represents the sixth leading cause of cancer death in Europe, where approximately 136,000 cases are diagnosed annually.
Most cases are diagnosed in the advanced stage, with a five-year global survival rate of 5% to 10% for advanced or metastatic disease, but survival remains modest even when diagnosed in the earlier stages of the disease.
Recommended first-line treatment in the EU for HER2-positive advanced or metastatic gastric cancer, which represents approximately one in five cases, is combination chemotherapy plus trastuzumab, an anti-HER2 medicine shown to improve survival outcomes when added to chemotherapy.
Prior to this latest approval of Enhertu, there were previously no other approved HER2-directed medicines in the EU for patients with metastatic gastric cancer that progresses following initial treatment with a trastuzumab-based regimen.
“Patients across the EU with advanced HER2-positive disease who have progressed following treatment in the first-line setting, may now have the opportunity to benefit from treatment with Enhertu,” said Dave Fredrickson, executive vice president of the oncology business unit at AstraZeneca.